Delft University of Technology
Escaping the emotional blur
Design tools for facilitating positive emotional granularity
Yoon, Jay DOI 10.4233/uuid:5f807568-492b-40eb-8618-bcdf1e1b2e7c Publication date 2018 Document Version Final published version
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Yoon, J. (2018). Escaping the emotional blur: Design tools for facilitating positive emotional granularity. https://doi.org/10.4233/uuid:5f807568-492b-40eb-8618-bcdf1e1b2e7c
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JungKyoon Yoon
Escaping
the emotional blur:
Design tools for facilitating
positive emotional
Escaping the emotional blur
Design tools for facilitating positive emotional granularity
Proefschrift
ter verkrijging van de graad van doctor aan de Technische Universiteit Delft,
op gezag van de Rector Magnificus prof.dr.ir. T.H.J.J. van der Hagen; voorzitter van het College voor Promoties,
in het openbaar te verdedigen op
donderdag 11 januari 2018 om 15:00 uur door
Jungkyoon YOON
ingenieur Industrieel Ontwerpen geboren te Seoul, Zuid-Korea
Dit proefschrift is goedgekeurd door: Promotor
Prof.dr.ir. P.M.A. Desmet Copromotor
Dr.-Ing. A.E. Pohlmeyer
Samenstelling promotiecommissie:
Onafhankelijke leden:
JungKyoon Yoon
Escaping the emotional blur: Design tools for facilitating positive emotional granularity ISBN: 978-94-6186-881-7
Cover design: Hyoungwoo Kim of Clay © JungKyoon Yoon, 2018.
All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, electronical or mechanical, including photocopying, recording or by any information storage and retrieval system without permission from the author. This research was supported by the MAGW VIDI, grant number 452-10-011, of The Netherlands Organization for Scientific Research (N.W.O.) awarded to P.M.A. Desmet. Rector Magnificus
Prof.dr.ir. P.M.A. Desmet Dr.-Ing. A.E. Pohlmeyer
voorzitter
Technische Universiteit Delft, promotor Technische Universiteit Delft, copromotor
Dr.ir. G.D.S. Ludden Dr. D.A. Sauter Prof. J. Zimmerman Prof.ir. D.N. Nas Prof.dr. P.P.M. Hekkert Universiteit Twente
Universiteit van Amsterdam Carnegie Mellon University Technische Universiteit Delft Technische Universiteit Delft
Some products are routinely described by the “feeling good” or “joyous”, but what lies beneath these words?
Table of contents
1.
Introduction
1
1.1.
Research overview 2
1.2.
Research approach 4
1.3.
Research outcome 5
1.4.
Outline of the thesis 8
1.5.
References 10
2.
What are positive emotions and how can they be
differentiated?
13
2.1.
What makes positive emotions positive? 14
2.2.
How does a positive emotion differ from other positive affective states? 16
2.3.
What is the function of positive emotions? 18
2.4.
How can positive emotions be differentiated? 20
2.5.
How are positive emotions experienced in human-product interactions? 24
2.6.
Towards designing for nuanced positive emotions 27
2.7.
References 28
3.
When ‘feeling good’ is not good enough: Seven key
opportunities for emotional granularity in product
development
33
3.1.
Introduction 34
3.2.
Four facets of emotional intelligence 38
3.3.
Identifying opportunities to work with PEG 41
3.4.
Results 47
3.5.
General discussion 54
3.6.
Conclusion 60
3.7.
References 61
4.
The mood street: Designing for nuanced positive
emotions
65
4.1.
Introduction 66
4.2.
Nuances of positive emotions 68
4.3.
Design case—Mood street project 68
4.4.
Design approach 69
4.5.
Examples of the concepts 74
4.6.
Lessons learned 77
4.7.
General discussion 82
4.8.
References 85
5.
Embodied typology of positive emotions: The
development of a tool to facilitate emotional
granularity in design
89
5.1.
Introduction 90
5.2.
Development of embodied typology of positive emotions 91
5.3.
Applications of the developed tool in a design process 100
5.4.
Conclusion and general discussion 103
5.5.
References 105
5.6.
Appendix 1: Appraisal literature reviewed for formulating eliciting conditions 107
6.
Developing usage guidelines for a card-based design
tool: A case of the positive emotional granularity
cards
109
6.1.
Introduction 110
6.2.
The positive emotional granularity cards 113
6.3.
Design case: Development of the PEG card guidelines 115
6.4.
General discussion 123
6.5.
References 125
7.
EmotionPrism: A design tool that communicates 25
pleasurable human-product interactions
129
7.1.
Introduction 130
7.2.
Considerations for the tool development 131
7.3.
Development of EmotionPrism 134
7.4.
Application of EmotionPrism 144
7.5.
General discussion 150
7.6.
Conclusion 152
7.7.
References 153
8.
‘Feeling good’ unpacked: Developing design tools to
facilitate a differentiated understanding of positive
emotions
157
8.1.
Introduction 158
8.2.
Approach 159
8.3.
Developing design tools 160
8.4.
Assessing the tools 166
8.5.
Results 168
8.6.
Discussion and conclusion 173
8.7.
References 175
9.
General discussion
177
9.1.
Discussion of the research findings 177
9.2.
Implications of the research 187
9.3.
Future research direction 191
9.4.
References 193
Summary
197
Acknowledgements
211
1. Introduction
Early this year, the movie-streaming service Netflix hinted at a plan to ditch its five-star movie rating system (McAlone, 2016). Over the years the company has come to realise that the star, which is meant to symbolise ‘fun’, is often interpreted as meaning something different, making its user ratings unreliable. For example, if you had fun watching a comedy movie you may give it a five-star rating because it made you laugh. However, others who were equally entertained watching the same film may
nevertheless give it the lowest ratings possible because its black humour was too sarcastic. The problem is that even if the star is presented literally as denoting ‘enjoyment’ or ‘fun’, the rating system remains misleading. Imagine a documentary film that is a bit dry or sad, but intellectually fulfilling to watch. If the ratings are based solely on how much fun people get out of it, the system will think that the film failed to amuse people, doing injustice to the different kind of enjoyment it facilitates.
Confusion caused by ambiguous representations also seems to occur when designing for emotion. In emotion-driven design, most designs aim to make people feel good. However, if we simply aim for ‘feeling good’, the design process may cause misunderstanding amongst members of the design team, clients and/or users because, like the Netflix stars, ‘feeling good’ is too blurry to serve as a design direction because it leaves room for many different interpretations. There is a multitude of pleasant emotions, such as relaxation, pride and fascination, each of which has different effects on users’ feelings, thoughts and behaviour. Recognising their differences and being precise about the intended emotional impact will surely help to minimise confusion and enable designers to appropriately target the experience desired by their clients and/or users.
1.1.
Research overview
Our emotional states (both positive and negative) can strongly influence our perceptions, decision-making and behaviour, which has ramifications for how we interact with products and services. For this reason user emotion has received much attention in design research, with affective states emerging as a key variable when designing for experiences and well-being (e.g., Desmet, 2002; Gaver, 2009; Hassenzahl, 2010; McCarthy & Wright, 2004). Various studies have contributed to our understanding of how knowledge of emotion can be incorporated into design processes (see Desmet & Hekkert, 2009 for an overview). Much of the emotion research in design is grounded in psychology, explaining what causes emotions to occur and how they can be classified. This is reasonable in that the underlying process of human emotions is universal (Frijda, 2007), and thus is also applicable to emotions evoked by design. The only difference is that in design research the focus is on a particular type of emotional stimuli, i.e., products (Desmet, Fokkinga, Ozkaramanli, & Yoon, 2016). Many design tools and education materials have been built on sets of ‘basic emotions’ drawn from the psychology literature, typically including five to eight basic emotions. However, borrowing emotion classifications from psychology is not always appropriate or fully compatible with design when one takes the multitude of emotions in daily interactions into account1. In particular, positive emotions that are experienced in
response to products are far too diverse and mixed to be simply shoehorned into basic emotion sets (Desmet, 2002).
In my view, most approaches and frameworks in design do not adequately reflect the broad diversity of positive emotions. They tend to deal with a handful of positive emotions and are thus limited in the extent to which they help designers to distinguish the finer differences between positive emotions. Just as there are many ways of feeling bad because of products (e.g., disappointment because of the poor performance of a new computer
1 In daily interactions with a product, a host of different emotions are experienced during an unfolding usage and ownership episodes. For example, a fitness tracker that monitors one’s activity may inspire a person with its sophisticated features today, but the same person may be annoyed or frustrated by it tomorrow when realising that its obtrusive colour does not fit her outfit. The emotional relationship between the user and the product continuously emerges and evolves over time depending on in which contexts the product is placed, how it is used, how it is talked about and what meanings the user allocates to it (see Haddon, 2007 for a detailed discussion).
or irritation at a sudden failure in data retrieval), there are also many different types of feeling good. For example, we can be interested in a mobile phone game that features a novel user interface, feel relieved at completing a mission in a game that seemed impossible and be proud at being ranked top among fellow game players. While all these emotions are pleasant, each of them represents a different experience. Desmet (2012) found that people can experience at least 25 different positive emotions when interacting with products.
Making fine-grained distinctions between positive emotions can be compared to being a wine expert. Expert vintners are more aware of specific features of a wide range of wines (e.g., taste, age and grape type) and better at differentiating them using explicit classifications, than are novice vintners (Solomon, 1997). The advantage of having this expertise is that they are able to describe the unique qualities of wines in detail and choose the right one for a particular situation. Similarly, having a broad repertoire and an in-depth understanding of positive emotions may enable designers to select the most appropriate positive emotions to design for and to communicate those emotions clearly (e.g., design for pride and relaxation). Given the variety of activities involved in the design process (e.g., user research and design conceptualisation), it is expected that distinguishing nuances between positive emotions could open up a number of new opportunities for designers.
Just as we are not all equally good at distinguishing between wines, not all people are equally sensitive to nuances between positive emotions2. This
individual difference is called Positive Emotional Granularity (PEG). PEG refers to “the tendency to communicate experiences of positive emotions with precision and specificity” (Tugade, Fredrickson, & Feldman Barrett, 2004, p. 1162). For example, an individual with high PEG articulates the distinctiveness of an emotional state (e.g., ‘I felt confident with a hint of pride’). In contrast, those lower in granularity tend to express their emotions with less distinct terminology (e.g., ‘I was feeling good’).
2 The literature on alexithymia suggests that the inability to differentiate emotions is a common symptom. Alexithymia is described as a trait in which individuals have
difficulty in distinguishing and elaborating emotions, and communicating them to others (Taylor, 1984). The prevalence rate of alexithymia was estimated to be about 10% in a large sample of the Finnish population (Salminen, Saarijärvi, Äärelä, Toikka, & Kauhanen, 1999).
Recent studies in psychology have transcended the traditional focus on generalised pleasure and generated insights into the characteristics of a set of distinct positive emotions (see Tugade, Shiota, & Kirby, 2014 for an overview). Several studies have been published that explain differences regarding expressions, causes and behavioural impact (e.g., Diener, 2009; Sauter, 2010; Tong, 2014). However, ways of supporting the PEG of designers, and the practical benefits to design processes of doing so, have received little attention in design research and education.
I propose that designers can benefit from having a fine-grained overview of positive emotions and the ability to make use of this knowledge in their design decisions. Building on this proposition, the present research aims to develop an understanding of how designers can be supported to systematically consider diverse and nuanced positive emotions in design processes, and how this can contribute to effective design processes. The project seeks to answer four related and consecutive research questions: 1. What are the opportunities for PEG in design processes?
2. What are the challenges that designers face when designing for nuanced positive emotions, in practice?
3. How can the PEG of designers be facilitated?
4. What are the strengths and limitations of strategies to facilitate PEG? This research contributes to the field of experience design by elucidating how PEG adds value to design processes and how designers’ PEG can be effectively facilitated. In addition, the research has generated a set of concrete design tools that designers can use when designing for nuanced positive emotions. The following sections briefly describe the research approach and outcome, followed by an outline of the thesis.
1.2. Research approach
This research builds on literature from design research and psychology. Theories on positive emotions and PEG have been combined with
technical knowledge and research methods in design research. Table 1.1 provides the key overview of the thesis structure, setup of the research project and main outcomes.
The thesis reports on a total of eight studies (studies A to H), in which various research methods—both qualitative and quantitative—have been triangulated to address the research questions. Interviews were
conducted to gain insights into the practical value of PEG in design processes (research question 1); a case study was employed to identify when and what types of challenges designers would encounter in the process of designing products that evoke nuanced positive emotions (research question 2); strategies to facilitate PEG were explored by iterations of developing and testing prototypes of design tools. The iterations involved several methods such as design workshops,
performances with actors and surveys (research question 3); and a focus group set-up with design experts was used to examine the usefulness of the strategies in supporting particular design activities (research question 4).
Since little was known about how designers’ PEG can be fostered, the decision was taken to develop an understanding through the
considerations, inspiration and reflections that emerged throughout the iterations of building and testing design tools. The overarching approach encompassing the research activities was ‘research through design’, where the act of designing new solutions and reflecting on the processes involved is regarded as a means of generating knowledge (Stappers, 2007). A series of tools and techniques was conceptualised for research purposes, and tested with designers in the contexts of both design education and practice.
1.3. Research outcome
The research has generated insights into when and how PEG becomes useful in design processes, how designers can create products that evoke nuanced positive emotions and how designers’ PEG can be stimulated. The insights gained from the research emerged from, and reside in, the resulting design tools, each of which reflects different strategies to convey nuances between positive emotions and the situations in which they are used. The developed tools have been applied in several design projects, conducted in both design practice and education contexts (studies B, E and G). In the process of developing and evaluating them, a series of additional research outcomes has emerged, ranging from certain elements incorporated into the tools to an approach to creating tool usage guidelines. The columns ‘tool’, ‘main outcome’ and ‘supporting content’ in Table 1.1 describe the deliverables of the research in detail.
Table 1.1. Thesis overview
RESEARCH QUESTION STUDY CHAPTER
2
What are positive emotions and how can they be differentiated?
Research question 1
What are the opportunities for emotional granularity in design processes?
A
An interview study that explores how designers can benefit from positive emotional granularity
3
When feeling good is not good enough: Seven key opportunities for emotional granularity in product development
Research question 2
What are the challenges that designers face when designing for nuanced positive emotions in practice?
B
A case study that investigates the challenges in eliciting nuanced positive emotions
4
The mood street: Design for nuanced positive emotions
Research question 3
How can positive emotional granularity be facilitated by means of design tools?
C
Literature review on general conditions that evoke a set of
positive emotions 5 Embodied typology of positive emotions: The development of a tool to facilitate emotional granularity in design D
Collection and validation of visual representations that display behavioural manifestations of positive emotions
E
Three design workshops that evaluate the positive emotional granularity cards
6
Developing usage guidelines for a card-based design tool: A case of the positive emotional granularity cards
F
Generation and validation of movies that express positive emotions in interactions with products
7
EmotionPrism: The development of a design tool that
communicates 25 pleasurable human—product interactions
G
A design workshop that evaluates the EmotionPrism tool
Research question 4
What are the strengths and limitations of the ways of facilitating PEG in design processes?
H
A focus group investigating strengths and weaknesses of different design tools with respect to their applicability in a design process
8
’Feeling good’ unpacked: Developing design tools to facilitate a differentiated understanding of positive emotions
9
TOOL MAIN OUTCOME SUPPORTING CONTENT A theoretical foundation for the
phenomenon of positive emotions
Seven key opportunities to work with positive emotional granularity in product development processes
An overview of the types of emotional intelligence that elucidates the place of emotional granularity
Implications for research on facilitating emotional granularity in design
Recommendations for developing a design tool to facilitate emotional granularity Nine lessons that discuss the
challenges involved in designing for nuanced positive emotions and how they can be overcome
An overview of appraisal approach and design process in the case study
Design examples that aim to evoke different positive emotions
The positive emotional granularity cards
Core relational themes of positive emotions
Application possibilities for the positive emotional granularity cards in a design process A set of validated visuals of
behavioural manifestations of positive emotions
Usage guidelines for the positive emotional granularity cards
A set of instructions for using the positive emotional granularity
cards An approach to developing usage guidelines for a card based design tool
A set of improvement recommendations for the design
The EmotionPrism
A set of validated videos that express positive emotions in
hand—object interactions An overview of thought—action tendencies of positive emotions Insights about the usefulness of
EmotionPrism The positive emotional
granularity cards, the EmotionPrism, and four additional design tools (an audio library of user anecdotes and three interactive installations)
Insights about when and how the four developed tools could be applied in design processes and their strengths and weaknesses
Introduction of the two additional design tools
1.4. Outline of the thesis
This thesis is composed of a series of scientific publications in
conjunction with two introductory and one concluding chapters. The body of the thesis consists of three journal papers and four peer-reviewed conference papers. These chapters were co-authored by the promotor and co-promotor of the research; the author of this thesis is the first author of all papers and responsible for the study designs, data analyses,
interpretation and writing. As shown in Table 1.1 there are six entry points for reading the thesis, allowing readers to choose the chapters most pertinent to their respective interests: (1) research question, (2) study, (3) chapter, (4) tool, (5) main outcome and (6) supporting content. Chapters are ordered according to the research questions.
Chapter 2 addresses the question of what positive emotions mean and how they can be differentiated. The literature on the phenomenon of positive emotions is discussed, serving as a starting point for the theoretical and empirical work expounded upon in this thesis. Chapter 3 addresses the first research question relating to the
opportunities for PEG, through an interview study (study A) that explored the potential benefits of PEG in product development processes. The chapter describes when and how PEG becomes useful for designers, and what kinds of PEG supports designers want. This study’s results served to specify the foci of the tool development phase of the research.
Chapter 4 addresses the second research question, which tackles the challenges of designing for nuanced positive emotions in practice with a focus on how design activities can be supported to evoke nuanced
positive emotions. Reflecting on the process of a design case study (study B), the chapter discusses the challenges involved in design activities and how they can be overcome. The results generated initialinsights into how nuances between positive emotions can be conveyed to designers and how such knowledge can be applied to design activities.
Chapters 5, 6 and 7 address the third research question, exploring ways in which designers can be supported in PEG through the development and evaluation of PEG tools. Chapter 5 presents ‘positive emotional
granularity cards’, a design tool that describes characteristics of distinct positive emotions. The cards were created as a versatile research tool; they served as a stimulus to probe designers’ expectations and needs in PEG tool use. In the chapter the development process is described in detail, along with the application possibilities of the cards in a design
project (studies C and D).
Chapter 6 reports on three design workshops in which the positive emotional granularity cards were used for three different design activities (study E). The study focused on understanding designers’ situational needs in tool applications and how they can be supported to make full use of the tool to fit their purposes. The added value of provisional tool usage guidelines is discussed and an approach to developing usage guidelines that incorporate designers’ needs and their own creative techniques presented. The findings inspired design directions for additional design tools.
Chapter 7 reports on the development and evaluation of ‘EmotionPrism’, a tool that communicates the expressive interaction qualities of positive emotions. The development of the tool was inspired by designers’ need for an overview of how positive emotions differentially influence the way a user interacts with a product (from studies A and B). The chapter reports on study F, which explored whether positive emotions in human-product interactions can be characterised by distinct and observable expressions. This also served as the basis for tool development. A design workshop in which the tool was applied opened discussion on its usefulness and limitations (study G).
Chapter 8 addresses the fourth research question, concerning the strengths and weaknesses of strategies to facilitate PEG. The chapter presents a comparative overview of four different design tools, each of which employed a different strategy to facilitate PEG. The tools served as research means in a focus group (study H), by which their strengths and weaknesses with regard to their applicability were analysed. The study generated insights into when and how each of the strategies becomes useful to convey nuances between positive emotions.
Finally, the thesis closes with Chapter 9 in which the key findings of the studies and issues for additional research are discussed. The implications of the research are presented with directions for future work.
1.5. References
Desmet, P. M. A. (2002). Designing emotions. Delft, the Netherlands: Delft University of Technology.
Desmet, P. M. A. (2012). Faces of product pleasure: 25 positive emotions in human-product interactions. International Journal of Design, 6(2), 1–29.
Desmet, P. M. A., & Hekkert, P. (2009). Special issue editorial: Design & emotion. International Journal of Design, 3(2), 1–6.
Diener, E. (Ed.). (2009). Assessing well-being: The collected works of Ed Diener. Dordrecht, the Netherlands: Springer.
Gaver, W. (2009). Designing for emotion (among other things). Philosophical Transactions of the Royal Society of London B: Biological Sciences, 364(1535), 3597– 3604.
Haddon, L. (2007). Roger Silverstone’s legacies: domestication. New Media & Society, 9(1), 25–32.
Hassenzahl, M. (2010). Experience design: Technology for all the right reasons. Morgan & Claypool.
McAlone, N. (2016). Netflix wants to ditch its 5-star rating system. Business Insider. Retrieved from http://uk.businessinsider.com/netflix-wants-to-ditch-5-star-ratings-2016-1
McCarthy, J., & Wright, P. (2004). Technology as experience. Interactions, 11(5), 42–43. Salminen, J. K., Saarijärvi, S., Äärelä, E., Toikka, T., & Kauhanen, J. (1999). Prevalence of alexithymia and its association with sociodemographic variables in the general population of Finland. Journal of Psychosomatic Research, 46(1), 75–82. Sauter, D. (2010). More than happy: The need for disentangling positive emotions. Current Directions in Psychological Science, 19(1), 36–40.
Solomon, G. E. A. (1997). Conceptual change and wine expertise. Journal of the Learning Sciences, 6(1), 41–60.
Stappers, P. J. (2007). Doing design as a part of doing research. In R. Michel (Ed.), Design research now (pp. 81–91). Basel, Switzerland: Birkhäuser Verlag AG.
Taylor, G. J. (1984). Alexithymia: Concept, measurement, and implications for treatment. American Journal of Psychiatry, 141(6), 725–732.
Tong, E. M. W. (2014). Differentiation of 13 positive emotions by appraisals. Cognition & Emotion, 29(3), 484–503.
Tugade, M. M., Fredrickson, B. L., & Feldman Barrett, L. (2004). Psychological resilience and positive emotional granularity: Examining the benefits of positive emotions on coping and health. Journal of Personality, 72(6), 1161–1190.
Tugade, M. M., Shiota, M. N., & Kirby, L. D. (2014). Introduction. In M. M. Tugade, M. N. Shiota, & L. D. Kirby (Eds.), Handbook of positive emotions (pp. 1–10). New York, NY: The guilford press.
2. What are positive emotions
and how can they be
differentiated?
A wide variety of theories and definitions of emotion has been proposed by emotion researchers (c.f., P. R. Kleinginna Jr. & Kleinginna, 1981).
Research on emotions in areas as diverse as philosophy, psychology, neuroscience and design has focused on different emotion phenomena. Accordingly, there appears to be no formalised definition that can be applied to any kind of emotion research. Nevertheless, there is an emerging consensus in psychology that emotions are conceptualised as brief and involuntary subjective experiences that are accompanied by multi-componential responses that enable people to adapt to the opportunities and challenges derived from a stimulus event (Scherer, 2005). The components are feelings (subjective experience of the emotion), appraisal (evaluation of objects and events), expressive
behaviour (communication of reactions like facial and vocal expressions), physiological responses (bodily changes like heartbeat, sweating and muscle tension) and instrumental behaviour (thought and action tendencies, like approach and avoidance) (for an overview, see Moors, 2009; Scherer, 2005). In the current research, I adopt the multi-componential view of emotions because of its usefulness in
systematically considering several facets of an emotion and relationships between emotions.
So far, I have not explicitly described what exactly ‘positive emotion’ means. From our experiences, we all intuitively know what a positive (and a negative) emotion is, and what it feels like to have a positive emotion— an experience that puts a smile on our face. In everyday life, we do not need to theoretically conceptualise the nature of positive emotions. However, in a research context it is not sufficient to rely solely on our implicit understanding of positive emotions. Nonetheless, design researchers often rely on intuitive definitions without conceptual precision, using ‘positive emotion’ as a unitary umbrella term to refer to any kind of subjective experience considered pleasant or the opposite of painful. As a consequence, the resulting research outcomes (e.g., design
methods and tools) tend to overlook important differences between positive emotions and other affective states (e.g., positive mood) (c.f., Desmet, 2015). Besides, different people have different ideas about what makes a positive emotion positive (Carver, 2010). The positive versus negative distinction, as well as distinctions between positive emotions, have been infused with a variety of different theoretical perspectives. As a consequence, various sets of positive emotions have been proposed (Kirby, Tugade, & Shiota, 2014b).
Given the goal and its approach of this thesis, in which design tools are developed, it is important to specify how positive emotions are defined and how they can be differentiated. For this reason, five basic questions are addressed that have served as a starting point for the theoretical and empirical work of this thesis: (1) what makes positive emotions positive?, (2) how do positive emotions differ from other positive affective states?, (3) what is the function of positive emotions?, (4) how can positive emotions be differentiated?, and (5) how are positive emotions experienced in human-product interactions?
2.1. What makes positive emotions positive?
Several ways of making a distinction between a positive and a negative emotion have been proposed, reflecting diverse theoretical perspectives. There are three widely accepted perspectives that can be considered either individually or combined: cognitive, behavioural and experiential. First, the cognitive perspective is based on the proposition that emotions are elicited by an appraisal of a situation (Smith, Tong, & Ellsworth, 2014). Appraisal refers to a direct and immediate sense judgement of the significance of a stimulus (e.g., event, object or thought) in relation to the person’s well-being (Frijda, 2007; Lazarus, 1991). In this perspective, an emotional state can be defined as positive when the individual appraises the stimulus as being beneficial (or non-threatening). In contrast, negative emotions are evoked by stimuli that are appraised as being unbeneficial. Second, the behavioural perspective emphasises the behavioural effects of emotions, distinguishing positive from negative emotion according to two aspects (Watson, Wiese, Vaidya, & Tellegen, 1999). One, is that the behaviour incited by positive emotions involves ‘approach’ and those sparked by negative emotions yield ‘avoidance’. The other, is that whereas positive emotions result in favourable (i.e., desirable or honourable) behaviour (e.g., sharing one’s resources), negative emotions result in
unfavourable behaviour (e.g., intimidating someone) (Averill, 1975). Third, the experiential perspective focuses on the experience of valence, a subjective sense of positivity or negativity accompanying the experience (Smith & Ellsworth, 1985); positive emotions are felt to be pleasant, negative emotions unpleasant.
It is important to note that an emotion that is classified as positive by one of the three perspectives, might not be similarly classified by another. Anger, for example, is typically considered a negative emotion from a cognitive and experiential perspective, but studies of the behavioural perspective have shown that anger stimulates a strong approach and confrontation tendency (e.g., Kirby, Morrow, & Yih, 2014a). From a cognitive perspective, hope is usually classified as a positive emotion because it occurs when a situation is perceived to be optimistic (Scherer, 2001). However, hope is not necessarily always felt to be pleasant, as the experience of it connotes an unguaranteed promise. Moreover, there are atypical instances in which negative emotions like fear and distress are felt to be pleasurable (Wilson-Mendenhall, Barrett, & Barsalou, 2013). Examples include the energising fear aroused by a rollercoaster or the spirited distress evoked by a sarcastic remark that makes a mean colleague skulk away3.
Some emotions, such as joy, relaxation and satisfaction, are obviously regarded as positive. However, some, such as hope and compassion, are at the fringes of the distinction between positive and negative emotions. Given the aim of the current research, I am interested in these nuanced positive emotions too. For the current research, it was decided to use an eclectic approach. Emotions were regarded as positive if they satisfied at least two of the following criteria: (1) the emotions involve pleasant feelings, (2) the stimuli are appraised as being beneficial (or non-threatening) to oneself, and (3) the emotions result in beneficial
behaviours for oneself or others. For example, the emotion compassion is considered positive in this research; it may not feel pleasant (i.e., the first criterion), but the situation could be appraised as being non-threatening because the sufferers’ distresses are not inflected on oneself (i.e., the second criterion), and the emotion motivates the person to help the
3 While interesting, atypical negative emotions are not considered positive in this research because while pleasant, negative emotions occur as antecedents of experiences, which is not the focus of the research.
sufferers (i.e., the third criterion) (Lazarus, 1991).
2.2. How does a positive emotion differ from other
positive affective states?
To refer to a pleasant experience, we often use terms like positive
emotions, good mood and sensorial pleasure interchangeably. Sometimes these terms are used with no explicit distinction in research contexts as well (e.g., Isen, 2000). In contrast, some researchers have argued that while these terms sound alike, not all of them can be considered positive emotion (e.g., Fredrickson & Branigan, 2001).
2.2.1. Positive emotion versus sensory pleasure
Positive emotion and sensory pleasure are closely related and the distinction between the two has often remained unarticulated. Sensory pleasure refers to the pleasure aroused through sensory modalities such as visual, auditory, olfactory, gustatory and tactile experiences
(Fredrickson & Cohn, 2008). Sensory pleasure includes, for example, the sweet taste of chocolate, the pleasant rustling sound of the wind in the trees, the fruity smell of one’s shampoo and the smooth silky touch of a duvet. Among emotion researchers, there is no general consensus as to whether or not sensory pleasure can be considered a positive emotion (for an in-depth discussion, see Ekman, 2012). In the present research, I adopt the view of Desmet (2012), which understands sensory pleasure as one way in which positive emotions are experienced, i.e., a source of positive emotion4. Several studies on positive emotions in human-product
interactions have shown that positive emotions often arise through direct sensation (e.g., Demir, Desmet, & Hekkert, 2009; Desmet, 2002; Norman, 2004). For example, on a hot day an air conditioner would freshly cool off the sweat and heat (i.e., sensation), which may lead to feelings of joy, satisfaction or relaxation (i.e., positive emotion). In other words, in this thesis, sensation itself is not considered to be an emotion but rather a subjective experience that can (but does not necessarily) act as a stimulus that evokes a full-blown emotion.
4 There are six basic sources of positive emotions in human-product interactions (Desmet, 2012). Positive emotions can be evoked by (1) the sensory properties of an object, (2) meaning associated with the object, (3) interaction with the object, (4) activity facilitated by the interaction, (5) oneself interacting with the object, and (6) other people involved in the interaction.
Positive emotion versus positive mood
Positive emotion and positive mood are similar affective experiences because both involve transient subjective feelings and can strongly influence people’s perception, behaviours and attitudes (Kelley & Hoffman, 1997). While analogous, they differ in terms of what causes them, how long they last and how explicitly they are recognised.
Emotions are acute and typically evoked by explicit causes (e.g., events, thoughts and memories), but moods have diffuse or a number of combined causes, not being directed towards specific stimuli (Ekman, 2012).
Because of this, we often do not know and are unable to articulate why we are in a particular mood (e.g., cheerful and relaxed mood). In contrast, it is usually possible to work out what has caused a certain positive emotion (Frijda, 2007); we know what makes us proud, what satisfies us and what interests us. Another key difference is that emotions are much shorter than moods, lasting at most seconds or minutes. The duration of moods can be all day or sometimes a few days (Beedie, Terry, & Lane, 2005). While emotion and mood are different, they are not mutually
independent. Both influence each other in terms of what they elicit (Fredrickson & Branigan, 2001). When in a cheerful mood, for example, we are more likely to experience a feeling of joy in relation to an event that does not typically make us feel joyful. Similarly, emotions also influence mood states. A person who frequently experiences positive emotions is likely to be in a cheerful or excited mood.
Figure 2.1. Affect, positive emotion and positive mood (adapted from Robbins, Judge, & Campbell, 2012, p. 261)
Affect
A broad range of feelings that people experience. Positive emotion
• Caused by specific event • Very brief in duration (seconds
or minutes)
• Specific and numerous (distinct positive emotions such as joy, kindness, interest and confidence)
Positive mood • Cause is often general and
unclear
• Last longer than emotions (hours or days)
• More general distinction between positive mood
The current research aims to support designers’ explicit understanding of positive emotions in their practices. The rationale for looking specifically at emotion rather than other affective states is that the explicit
relationship between an emotion and its cause makes it possible for designers to address emotion through their products as stimuli (Desmet, 2002). The research aim goes beyond offering a range of verbal
descriptions of positive emotions; the multifaceted qualities of distinct positive emotions, such as when and how the emotion arises and how it influences an individual’s behaviour, need to be clearly communicated to designers. Although positive moods are an interesting subject to study, their inclusion would not particularly contribute to the research;
differences between positive moods are elusive in terms of their causes, and the relationship between positive mood states and their effects on user behaviours is indistinct. Therefore, it was decided not to include differentiated positive mood states in the current research.
2.3. What is the function of positive emotions?
Positive emotions such as love, kindness, pride, admiration and
fascination, are not just words that we use. Even though these emotions are subtle and short-lived, they are deeply felt and can incite changes in our thoughts and actions. For instance, one day at a flea market in Delft, in the Netherlands, I stumbled upon a vintage twin-lens reflex camera that had a peculiar structure. Fascinated, I immediately started exploring how it worked and why it was designed that way. The more I learned about the design, the more my interest in vintage cameras grew. Over the years I have collected a series of vintage cameras. This has allowed me not only to develop my knowledge but also to connect with a network of camera enthusiasts with whom I have shared a vast amount of information. The ‘broaden-and-build theory of positive emotions’ developed by Fredrickson (1998; 2003) suggests that positive emotions play an
essential role in building up our personal well-being resources. The theory begins with the immediate effects of positive emotions, which broaden our repertoire of thoughts and actions. This, in turn, enables our
behaviours to be open, flexible, explorative, adaptive and playful, leading to long-term effects of frequent positive emotions. Subsequently, the behaviours incited by positive emotions enable us to build resources (e.g., knowledge, social bonding) that make lasting contributions to our growth and well-being. For example, the physical play stimulated by joy can lead to long-term improvements in health while the strategies for play can foster intellectual resources, resulting in strengthened social
relationships (Sherrod & Singer, 1985). The knowledge and relationships gained through positive emotions like my experience with the vintage camera can also be explained by the theory. Figure 2.2 visualises the effects of positive emotions based on the broaden-and-build theory. Researchers have recently started exploring the differential effects of distinct positive emotions on people’s thoughts and actions, i.e.,
thought-action tendencies. For example, Sprecher and Fehr (2005) found that compassion induces people to be altruistic and less punitive in their social interactions; Algoe and Haidt (2009) showed that admiration spurs people into adopting the ideas and values of that someone (or something) they admire; and Worline, Wrzensniewski, and Rafaeli (2002) showed that courage motivates people to persist in pursuing their goals in the face of setbacks.
In line with studies on the effects of positive emotions, design researchers have started to explore if and how design can evoke specific positive emotions with the purpose of deliberately influencing user behaviour. For instance, Ludden, Schifferstein, and Hekkert (2012) used sensory
incongruity between visual and tactual experiences as a means of evoking pleasant surprise, which was found to have the long-term effect of stimulating further exploration of the product. Mugge, Schoormans, and Schifferstein (2008) used personalisation of a product as a strategy to facilitate a feeling of attachment, which can encourage its irreplaceability and prolonged use. It appears advantageous for designers to have an overview of thought-action tendencies associated with a range of positive emotions, because the ability to deliberately influence user behaviour is Figure 2.2. The broaden-and-build theory of positive emotions (adapted from Fredrickson & Cohn, 2008, p. 783)
Positive emotions
Novel thoughts, activities, relationships
Building enduring personal resources (e.g., social support, resilience, skills
and knowledge)
Enhanced health, survival, fulfilment
Broadening Produces more experiences of positive emotions, creating an upward spiral
one of the key motivations of designing for emotion (Desmet & Hekkert, 2009). Therefore, thought-action tendencies of positive emotions are comprehensively examined and used as a key component of tool
development in Chapters 5 and 7 of this thesis. In addition, the necessity of understanding the differential long-term impact of positive emotions is briefly discussed in Chapter 7.
2.4. How can positive emotions be differentiated?
2.4.1. Dimensional approach
Traditionally, differentiation of emotions has been studied using two approaches: the dimensional approach and the categorical approach (Zachar, 2012). The main assumption of models that follow the
dimensional approach is that emotions can be effectively described by and visually positioned within the continuous space structured by certain dimensions. These dimensions typically include measures of valence (pleasantness versus unpleasantness) and activation (high arousal versus low arousal). For example, the Positive Activation - Negative Activation (PANA) model (Watson & Tellegen, 1985) contains 20 emotions—ten positive (e.g., interested, strong and enthusiastic) and ten negative (e.g., jittery, hostile and ashamed)—classified along two dimensions. Another example is the circumplex model (Russell, 1980), in which emotions are organised in a circular shape (see Figure 2.3). In this model, ‘calm’, ‘relaxed’ and ‘serene’ fall into the pleasant-sleep segment, while ‘excite’, ‘delighted’ and ‘happy’ are placed within the pleasant-arousal segment. The dimensional approach has been widely applied to the development of design tools that address emotional experiences, because of the
comprehensive way in which it structures emotions. For example, AffectAura (McDuff et al., 2012), a tool that monitors changes in a user’s emotional states, differentiates emotions along the dimensions of valence, arousal and engagement. The dimensional approach appears useful for presenting a quick overview of various emotions. However, it has been criticised for its limitation to make fine distinctions between emotions. Confidence and fascination, for example, are clearly different emotional states, but are seen as being almost identical when located on the dimensions of pleasantness and arousal (Nicolás, Aurisicchio, & Desmet, 2014). In short, with this approach there is a risk that some positive emotions are not clearly distinguishable. Given that the aim of the current research is to facilitate designers’ PEG, reducing the diversity of positive emotions to a few dimensions seems inappropriate.
2.4.2. Categorical approach
Under the categorical approach, emotion is regarded as a unique pattern of multi-component responses (e.g., appraisals, expressions, subjective feelings etc.), and as such emotions can be differentiated and categorised according to a particular emotion component (Fontaine, 2013). Recently, researchers have started exploring characteristics of distinct positive Figure 2.3. Emotions on the circumplex model of affect (adapted from Russell, 1980, p. 1169)
Figure 2.4. An example of design tools that have adopted the dimensional approach: AffectAura (McDuff, Karlson, Kapoor, Roseway, & Czerwinski, 2012)
•
Astonished•
•
Aroused•
Happy•
•
Glad•
•
•
Satisfied•
•
•
Serene At ease Calm•
Relaxed•
Sleepy•
Tired•
Droopy•
•
•
•
Sad•
•
•
•
•
•
•
•
Bored Gloomy Depressed Miserable Distressed Annoyed FrustratedAngry Afraid Alarmed Content Delighted Pleased Tense Excited AROUSAL SLEEP PLEASURE UNPLEASURE RELAXATION EXCITEMENT DISTRESS DEPRESSIONemotions based on various emotion components. For example, Tong (2014) classified 13 positive emotions in terms of their causes (i.e., appraisals), while Campos, Shiota, Keltner, Gonzaga, and Goetz (2013) investigated similarities between eight positive emotions based on expressive displays and causes.
These studies have shown that similarity between positive emotions differs depending on what kind of emotion component is selected as the criterion for differentiation. For example, contentment and joy are considered similar with regard to their eliciting conditions because both are experienced when a situation is appraised as being safe and
advantageous to reaching a goal. But, they are considerably different in terms of facial expressions and body postures (Campos et al., 2013). Using appraisal models in psychology, Desmet (2003) proposed five theoretical categories of product emotions focusing on eliciting conditions: surprise emotions, instrumental emotions, aesthetic emotions, social emotions and interest emotions. The classification emphasises the benefit to designers of being aware of the patterns that Figure 2.5. Typology of 25 positive emotions categorised in nine emotional types (adapted from Desmet, 2012)
Figure 2.6. An example of design tools that have adopted the categorical approach: PrEmo (Desmet, 2002; Laurans & Desmet, 2012)
EMPATHY AFFECTION ASPIRATION
Sympathy, Kindness,Respect Love, Admiration, Worship Dreaminess, Lust, Desire
ENJOYMENT OPTIMISM ANIMATION
Euphoria, Joy, Amusement Courage, Hope, Anticipation Surprise, Being energetic
ASSURANCE INTEREST GRATIFICATION
Pride, Confidence Inspiration, Enchantment,
underlie a wealth of different emotions to stimulate (or prevent) certain emotions through designs. More recently, Desmet (2012) introduced a typology of positive emotions that consists of 25 positive emotions categorised into nine clusters. The emotions were derived from a componential analysis of positive emotion lexicons, and the
categorisation was based on an empirical study that examined similarity between emotions in terms of a combination of appraisal, thought-action tendency and subjective feelings. All the emotions included were found to arise during product use.
The categorical approach has been applied to design tools to emphasise certain emotion components that are relevant to support specific design activities. One example that uses a categorical approach is the Product Emotion Measurement Tool (PrEmo) (Desmet, 2002; Laurans & Desmet, 2012), a non-verbal self-report tool for measuring the emotions of users. In the tool, 14 emotions (seven positive emotions) are differentiated by an animated character portraying them with facial and bodily expressions combined with vocal tones. The major advantage of the categorical approach is that positive emotions can be differentiated and compared according to certain emotion components, which enables the
multifaceted qualities of an emotion to be understood holistically. I therefore decided to adopt a categorical approach for looking into nuances between positive emotions. Because the typology of positive emotions is fine-grained yet concise, meeting the criteria set out in section 2.1, Desmet’s (2012) typology is applied in particular to the development of design tools. Although differentiation of positive emotions has been addressed in many studies, each study has focused on slightly different sets of positive emotions, making it difficult to gain a
comparative, fine-grained overview. Therefore, by adopting the
categorical approach and building on the typology of positive emotions, differentiated eliciting conditions of positive emotions (in Chapter 5) and thought-action tendencies of positive emotions (in Chapter 7) are comprehensively investigated.
2.5. How are positive emotions experienced in
human
-
product interactions?
To deliberately evoke particular emotions with design, it is important for designers to know under what conditions each of the different positive emotions is experienced, i.e., the emotion-specific eliciting conditions. The basic idea is that designers would be able to purposely evoke specific positive emotions by creating products that meet certain eliciting
conditions.
Several theoretical frameworks have been introduced to help understand Figure 2.7. The basic product emotion model that explains the underlying processes of emotion elicitations (adapted from Desmet, 2002)
Product Concern Appraisal Emotion Product Concern Appraisal Emotion Action camera I want to stay organised.
I could mount the camera without bulky accessories, which would make the shooting clutter-free. Satisfaction Product Concern Appraisal Emotion Action camera I want to express my creativity.
I imagine the unique and dynamic images
the camera will capture. Inspiration
Product Concern Appraisal Emotion Action camera I cherish the memories of my family trip.
The automatic backup function would enable me to keep and access all pictures.
how products evoke positive emotions. Using the psychological pleasure framework of Tiger (1992), Jordan (2000) distinguished four sources of product pleasure, while Desmet (2002) explained the general process by which product emotions arise, based on appraisal theory. In line with a neurobiological approach, Norman (2004) identified three sources of product emotions. Finally, Hassenzahl (2010) introduced six needs associated with positive experience relating to universal human needs. Although these frameworks have different theoretical backgrounds and use different terminologies, they share the idea that few one-to-one relationships between product properties (e.g., appearance, material, movement etc.) and emotions exist, and that emotional responses are in fact based on personal (and subjective) meanings derived from the product. In most cases, the types of emotion are not determined by the product itself, but by the personal concerns that influence how users interpret the product.
Desmet’s approach is particularly interesting for the purpose of the current research, because the appraisal perspective offers a way of understanding the underlying psychological process responsible for distinct emotional responses to a product. According to the basic product emotion model (Desmet, 2002), the type of user emotion is determined by an appraisal in which personal concerns act as a reference point. The concern that a user has when interacting with a product influences the way he/she appraises it, defining the resulting emotion (see Figure 2.7). This implies that differences in people’s emotional responses can be referred back to differences in the concerns they have (and how the stimulus is appraised to be relevant to these concerns). For instance, a user with a concern of being free from clutter may experience satisfaction with an action camera that can be easily installed anywhere without bulky accessories. For the same camera, a different user whose concern is for expressing creativity may experience inspiration because of the unique and dynamic images the camera can capture. Those who cherish the moments in which pictures are taken may feel relief because of the camera’s automatic backup function. The main advantage of the model is that it explains how nuanced positive emotions arise from product use and related variables, i.e., concerns, product and appraisal. Moreover, the process represented by the model is universal (Desmet, 2002). Given this advantage, in Chapter 4 of this thesis, the model serves as a theoretical framework for structuring a design process that aims to evoke nuanced positive emotions.
products themselves (Desmet, 2012). Positive emotions in human-product interactions can be either directly elicited by products or indirectly elicited by activities and interactions facilitated by the products. For example, people can be amused by a smart watch that has a funny or playful appearance, and they also can be fascinated by the designer’s creativity and skills expressed by the smart watch or by what other people can do with it. In other words, products themselves evoke positive
emotions, and they also provide contexts for emotions: activities, interactions and associations facilitated by them serve as sources of positive emotions. Desmet (2012) proposed six main sources of positive emotions based on a collection of example cases in which people experience positive emotions in human-product interactions: Object, meaning, interaction, activity, self, and other. The different sources can be summarised as follows:
• Object-focus: Positive emotions experienced in response to the material qualities of the product (e.g., appearance, taste, tactile quality, sound, and fragrance).
• Meaning-focus: Positive emotions experienced in response to associated or symbolised meanings of the product.
• Interaction-focus: Positive emotions evoked by how the product responds to the user when he/she is using it.
• Activity-focus: Positive emotions experienced in response to the activity enabled or facilitated by the product.
• Self-focus: Positive emotions experienced in response to ourselves; the effects of using or owing products. people are emotional about who they are and how others perceive them. • Other-focus: Positive emotions evoked by the effects of other
people’s activities on us, in which the product plays some role. In this focus, interactions with other people are influenced or facilitated by products.
These different sources of positive emotions imply that it is important to look beyond the material qualities of a product when designing for positive emotions and to search for different opportunities together, i.e., enabling, facilitating, or influencing the different sources by means of design. In Chapter 4 of this thesis, the six sources of positive emotions are used as a framework that guides designers to explore different ways to evoke a of distinct positive emotion when generating product ideas.
2.6. Towards designing for nuanced positive emotions
Traditionally, attention has been paid to user emotions particularly when design causes unpleasant experiences (Desmet & Hekkert, 2009). This has led the focus of design to be directed at avoiding negative emotions instead of intentionally stimulating and sustaining positive emotional experiences. That is changing, and there is now increasing emphasis on the role of positive emotions in design research (e.g., Desmet &
Pohlmeyer, 2013; Hassenzahl, 2010). I believe that designers can benefit greatly from developing an understanding of positive emotions. The critical roles that positive emotions play in perception, thoughts,
behaviour and, by extension, improved well-being, support the argument that designing for positive emotions is important. In particular,
distinguishing nuances between positive emotions illuminates a promising new direction in experience design. As a starting point, this section has discussed some of the key literature on the phenomenon of positive emotions. I have addressed the questions of how a distinction between a positive and a negative emotion can be made, how positive emotions differ from similar positive affective states, how positive emotions can be classified, what the functions of positive emotions are and what process underlies positive emotional responses to a product. The implications of all this for the current research were discussed, and relevant theoretical models and approaches were chosen, which will serve as a theoretical foundation for the work presented in the following
chapters. Now that an overview of the phenomenon of positive emotions has been achieved, the next step is to identify the practical relevance of differentiating positive emotions in the context of designing a product.
2.7. References
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